class Product < ActiveRecord::Base

   def self.find_products_for_sale
     find(:all, :order => "title")
   end



  validates_presence_of :title, :description, :image_url
  validates_numericality_of :price
  validate :price_must_be_at_least_a_cent
  validates_uniqueness_of :title
  validates_length_of :title, :minimum => 10,
 		      :message => 'title too short'
  validates_format_of :image_url,
 		      :with    => %r{\.(gif|jpg|png)}i,
		      :message => 'must be a URL for GIF, JPG' + 
				  'or PNG image.'

 protected
   def price_must_be_at_least_a_cent
     errors.add(:price, 'should be at least a 0.01') if price.nil? || price < 0.01
   end

end
